Spring starter for internal combustion engines



March 19, 1963 R. J. MAUCK ETAL 3,031,759

SPRING STARTER FOR INTERNAL COMBUSTION ENGINES Filed Aug. 19, 1960 3 Sheets-Sheet l N t. N

INVENTORJ' ZoZerz J. wax/f March 19, 1963 R. J. 'MAUCK ETAL 3,081,759

SPRING STARTER FOR INTERNAL COMBUSTION ENGINES Filed Aug. 19, 1960 3 Sheets-Sheet 2 NV NTORS. F 187; 42/0? 1 March 19, 1963 R. J. MAUCK ETAL 3,031,759

SPRING STARTER FOR INTERNAL COMBUSTION ENGINES Filed Aug. 19, 1960 3 Sheets-Sheet 3 INV NTORS 702677 J. dz/a/f .Q'ifidlfiS Patented Mar. 19, I953 3,931,759 SFRWG STARTER FUR INTERNAL CUM- BIETIQN ENGINES Robert I. Mauck, 315 W. Long Lake Road, Bloomfield Hills, Mich, and William P. Mauck, 5941 E. Millerway,

Birmingham, Mich.

Filed Aug. 19, 196i Ser. No. %,747 16 Claims. (Cl. 123-479) This invention relates to spring starters, and more particularly to hand-wound starters of the type suitable for use in starting internal combustion engines such as those used in lawn mowers and the like.

It is an object of the invention to provide a novel and improved spring starter which is of universal application, that is, is adapted to be mounted on any of the various types of internal combustion engines such as are now in use for lawn mowers and similar appliances.

It is a further object to provide an improved starter of this nature which can be simply and easily installed regardless of the relative positions of the engine crankshaft and engine housing, and may also be connected to various shapes of crankshaft ends.

It is a further object to provide an improved spring starter having the above characteristics, which can be wound and released by different movements of the same hand crank assembly, and in which the hand crank will be automatically disconnected from the spring before release can take place.

It is another object to provide an improved spring starter of the above type which is extremely compact, of pleasing appearance, and is economical to manufacture and easy to maintain.

Other objects, features, and advantages of the present invention will become apparent from the subsequent description, taken in conjunction with the accompanying drawings.

In the drawings:

FIGURE 1 is a cross-sectional view in elevation of the improved spring starter, taken along the line 1-1 of FIGURE 2;

FIGURE 2 is a plan view of the starter, parts being broken away, showing the locations of the mounting brackets and the configuration of the handle slot;

FIGURE 3 is a fragmentary cross-sectional View in elevation taken along the line 3-3 of FIGURE 2, and showing the interrelationship among the handle components;

FIGURE 4 is a top plan view of the shaft and attached center spring hub;

FIGURE 5 is a top plan view of the inner handle member;

FIGURE 6 is an end elevational view of the inner handle member taken in the direction of the arrow 6 of FIGURE 5;

FIGURE 7 is a fragmentary cross-sectional plan view taken along the line 77 of FIGURE 1, and showing the telescoping keyed connection between the shaft and inner clutch member;

FIGURE 8 is a detailed elevational view of the adaptor used to connect the outer one-way clutch member to any of various crankshaft sizes; and

FIGURE 9 is a cross-sectional plan view taken along the line 99 of FIGURE 1, with the dust covers removed, showing the coaction between the inner and outer one-way clutch elements.

In general terms, the invention comprises a housing enclosing a spiral le'af torsion spring, the inner end of the spring being connected to a shaft with the housing adapted to be mounted on an engine housing such as that found in lawn mowers. The upper end of the shaft carries a two-piece foldable hand crank, the inner crank member being slidable radially on the shaft between a winding position keyed to the shaft, and a release position disconnected from the shaft. The shaft carries a ratchet cooperating with a stationary pawl, and the inner crank member has a pawl release element engageable with the pawl when the crank is moved to its release position.

A one-way clutch for transmitting torque from the spring to the engine crankshaft is provided, this clutch having a novel adaptor permitting its use on any of various shapes of commonly known engine crankshafts. A keyed telescoping connection is provided between the clutch and the starter shaft so that the starter housing may be mounted at any of a range of heights with respect to the engine crankshaft, thus permitting the starter to be mounted on various makes of engines having different housing configurations.

Referring more particularly to the drawings, the spring starter is generally indicated at 11 and comprises a housing generally indicated at 12 of somewhat circular and inverted dish-shape. More particularly, housing 12 has a vertical side wall 13, an upper wall 14 and a lower outwardly extending flange 15. One portion 16 of the hous ing, seen in FIGURE 2, on the right-hand side, extends outwardly some distance for purposes described below. A bottom cover 17 is secured by rivets 18 and bolts 19 to flange 15, and the central portions 21 and 22 of wall 14 and cover 17, respectively, are apertured to receive a starter shaft generally indicated at 23, bushings 24 and 25 being provided in the apertures for rotatably supporting the shaft. Two center hub members 2&5 and 27 having a configuration seen in FIGURE 4, are secured to the central portion of shaft 23 within housing 12. A torsion leaf spring 28 is disposed within the housing, and the outer end 29 of the spring is secured by a pin 31 to housing 12, this pin being disposed in portion 16 of the housing. The inner end 32 of spring 28 is engageable by hubs 26 and 27 when the latter are rotated counterclockwise as seen in FIGURE 4. A spacer 33 is mounted below hub member 27 to limit axial movement of shaft 23.

Shaft 23 extends above housing 12, and has a reduced portion 34 providing a shoulder 35, as seen 'in FIG- URE 4. Portion 34 is flattened on opposite sides 36 and 37, and a ratchet 38 having a complementary center aperture 39 is non-rotatably mounted on shoulder 35 and around portion 34 of the shaft. A further reduced portion 41 at the upper end of shaft 23 is provided forming a shoulder 42, and flats 43 and 44 are formed on the opposite sides of shaft portion 41. A crank generally indicated at 45 is provided, this crank having an inner element generally indicated at 4-6 and an outer element generally indicated at 47. The configuration of inner element 46 is best seen in FIGURES 5 and 6, this element being of substantially channel-shaped cross-section, with a main flat portion 48, a pair of side flanges 4% and 51, and a central slot 52 having a narrow portion 53 and a wide portion 54. Slot portion 53 is adapted to coopcrate with flats 43 and 44 of shaft portion 41 when element 46 is moved to the extreme left, that is, slightly more to the left than is shown in FIGURES 1 and 2.

When in this position, rotation of the crank will cause rotation of shaft 23. When inner element 46 is moved to the right, shaft portion 41 will be disposed within the wider portion 54 of slot 52, so that the crank may rotate freely with respect to the shaft, and vice versa.

The left-hand end of crank element 46, as seen in FIG- URE 5, is provided with a pawl release element 55, this element being bent downwardly from the main portion of crank element 46 and having an S-shaped configuration as seen in FIGURE 5. The forward edge 56 of element 55 is adapted to engage a pawl 57 mounted on a 3 stationary pivot 58 secured to the top of housing 12, as seen in FIGURE 3. Pawl 57 is adapted to engage ratchet .38, and for this purpose is provided with a spring 59 is curved outwardly as seen in FIGURE 5 so as to be engageable with the hub portion 62 of pawl 57 seen in FIGURE 3, thus preventing further counterclockwise rotation of the crank. This provides a limit position for the release crank movement.

Outer crank element 47 is pivotally connected to the right-hand end of element 46, as seen in FIGURE 1, by a pin 63. Crank element 47 is swingable between an outer position shown in dot-dash lines in FIGURE 1 and a folded position shown in solid lines. Element 47 is of channel-shaped cross-section as seen in FIGURE 3,

the configuration being such that the channel shape will be open downwardly when the crank is folded. A cover 64 of inverted channel-shape, seen in FIGURE 3, is secured to inner element 46. The cover has a pair of ears 65 mounted on pin 63, and a tab 66 is struck upwardly from member 55 and is received by an aperture 67 in the left-hand end of cover 64 as seen in FIGURE 1. Outer crank element 47 encloses cover 64 when the crank is folded, as is illustrated in FIGURE 3.

A guide disk 68 is secured to the top of shaft 23 by a screw 69 threaded in a tapped hole 71 in the shaft. This disk is disposed between flanges 49 and 51 of crank element 46, so as to guide the element for radial sliding movement when shifted between its winding and release positions. A coil compression spring 72 surrounds shaft portion 34 and is engageable at its lower end with ratchet 38, a washer 73 being provided between the upper end of spring 72 and the underside of crank element 46. Spring 72 thus serves to hold ratchet 38 in position and prevent undesired movement of crank 45. A handle 74 is secured to the outer end of outer crank element 47, so that crank 45 may be manually rotated when outer crank element 47 is swung outwardly. A tab 75 on crank element 47 adjacent pin 63 is engageable with the underside of cover 64 when crank element 47 is swung outwardly, as seen in dot-dash lines in FIGURE 1 to limit this outward movement.

lStarter 11 is adapted to be mounted on the housing 76 of an internal combustion engine having a crankshaft 77 and a flywheel 78. In installations such as lawn mowers, crankshafts are usually vertically arranged, but the height of the top 79 of shaft 77 can vary considerably with respect to the top 81 of housing 76. The invention provides means for permitting starter 11 to be mounted on housing 76 regardless of this variation in height, starter shaft 23 being connected to crankshaft 77 by a novel interconnecting arrangement. A plurality of circumferentially spaced legs 82 of fixed height are provided, these legs having a C-shaped configuration as seen in FIGURE 3 with their upper portions 83 being secured to the underside of cover 17 and their lower portions 84 secured by bolts 85 to the top 81 of engine housing 76. A perforated annular shield 86 surrounds the space between cover 17 and housing 81 outside legs 82, to permit air to enter the engine.

A one-way clutch, generally indicated at 87, connects crankshaft 77 with starter shaft 2 3. This clutch has an outer clutch element generally indicated at 88 secured to crankshaft 77, and an 'inner clutch element generally indicated at 89 connected to starter shaft 23. An adaptor 91 illustrated in FIGURE 8 is used to connect clutch element 88 with shaft 77. This adaptor has a pair of external threads 92 and 93 at its opposite ends, these threads being identical with either thread receivable by thread 94 in the hub 95 of cup-shaped outer clutch element 88. Adaptor 91 has two internal threads 96 and 97 of different sizes. There are thus three different types of threads (94, 96 and 97) provided for cooperating with the threads 98 which are normally provided at the top of crankshaft 77. The starter 11 may thus be sold as a kit together with an adaptor 91, and if crankshaft thread 98 matches clutch hub thread 94-, the adaptor need not be used. If crankshaft thread 98 matches thread 96, thread 92 may be used to mount the adaptor in the clutch hub and the clutch then mounted on crankshaft 77. In this case, the other end of the adaptor 91 carrying threads 93 and 97 may be cut off to prevent interference with other parts later described. If crankshaft thread '98 matches internal thread 97 of the adaptor, adaptor thread 93 may be threaded into hub 95 and the other end of the adaptor cut off in a similar manner.

The construction of the cooperating portions of clutch elements 88 and 89 is best seen in FIGURE 9. Clutch element 88 has four pockets 99 and retains a ball 101. Clutch element 89 has a spiral surface 162 and a radial shoulder 103 engageable with ball 101 when element 89 is rotated clockwise as seen in FIGURE 9' to force the ball against straight wall 184 of clutch'element 88 between pockets 99. Counterclockwise rotation of clutch element 89 with respect to clutch element 88 will be freely permitted, ball 101 entering a pocket'99. A pair of dust covers or guards 105 and 106 are preferably mounted on clutch elements 88 and 89, respectively,as seen in FIGURE 1, to prevent or minimize the amount of dirt which may enter the one-way clutch.

Clutch element 89 has a portion 107 of square or other non-circular cross-sectional shape extending upwardly therefrom, and this portion is adapted to have a non-rotatable telescoping relation with a recess 108 of complementary shape in the lower end of shaft 23, as seen in FIGURE 7. The overlapping distance between clutch element 89 and shaft 23 is such as to provide a wide latitude for height differences between the top 81 of housing 76 and the top 79 of crankshaft 77, such as occurs in different makes of engines. While the height of housing 81 relative to crankshaft 77, shown in FIG- URE 1, is about the lowest that is commonly known, housing top 81 could be considerably higher, the result being simply that clutch extension 107 would not enter as far into recess 168. Shaft 23 would still be capable of driving clutch element 89 becauseof the non-circular cross-sectional shape of the telescoping elements.

A liner 109 of brass or other relatively soft metal is provided in a central aperture 111 of 'clutch element 89, this aperture being somewhat wider at the bottom than at the top, as seen in FIGURE 1. The purpose of liner 199 is to rotatably'engage the upper portion of adaptor 91, thus preventing unwarranted radial shifting of clutch element 89. In the case of some gasoline engines having an upper extension on their crankshafts, the upper portion of liner 109 is adapted to receive and rotatably engage such extension for a similar purpose.

In operation, assuming an initial condition in which spring 28 is unwound and it is desired to start the engine by rotating crankshaft '77, crank 45 will be unfolded and shifted to the left as seen in FIGURES 1 and 2, so that slot portion 53 of inner crank element 46 is engageable with flats 43 and 44 of shaft portion 41. When in this position, shaft -23 may be rotated in a counterclockwise direction as seen in FIGURE 2. Hub members 26 and 27 will engage the inner end 32 of spring 28, winding the spring. Pawl 57 will prevent unwinding of the spring during this winding movement by engagement with ratchet 38. Pawl release member 55 will rotate clear of pawl 57 as will be noted from FIGURE 2 and will thus not interefere with the winding movement. Clutch element 89 will rotate idly within clutch element 88 because of the counterclockwise rotation, as noted in FIGURE 9.

When spring 28 has been fully wound, crank 45 may be shifted to the right as seen in FIGURE 1 with outer crank member 47 still unfolded. As soon as the narrow portion 53 of slot 52 is withdrawn from shaft flats 43 and 44, crank 45 will be disconnected from shaft 23 so that the latter may rotate freely without driving the crank. At this point, however, shaft 23 will still be held against rotation, as urged by spring 28, by the engagement of pawl 57 with ratchet 38. When crank 45 has been pulled far enough to the right so that the lefthand end of slot portion 54 engages shaft portion 41, release member 55 will be in position to release pawl 57, as shown by the dot-dash lines in "FIGURE 2. The shifting of crank 45 to its release position may be accomplished in any rotational position of the crank, except in the position in which release member 55 by engaging the hub 62 of pawl 57 will prevent complete movement of the crank to its release position.

Assuming, however, that the crank has been fully shifted to its release position, further counterclockwise rotation, for example from the position shown in dot-dash lines in FIGURE 2, will cause edge 56 of member 55 to engage pawl 57, withdrawing the pawl from ratchet 38. This will permit spring 28 to rapidly spin shaft 23 in a clockwise direction as seen in FIGURE 2. Clutch element 89 will engage ball 16 1, forcing it against clutch element '83 to drive crankshaft 77, starting the engine. Member 55 cannot go past pawl 57 since portion 61 of member 55 will engage hub 62 of pawl 57, limiting the rotational movement of the crank. Once the engine starts, and spring 28 has been unwound, there will be no further rotation of shaft 23 because of one-way clutch 87. Crank 45 may then be folded, and either left in its release position or shifted leftwardly, as seen in FIGURE 1, to its winding position.

While it will be apparent that the preferred embodiment of the invention disclosed is well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. In combination, a spring starter having a housing, a spring within said housing, a shaft rotatably mounted in said housing and connected to said spring, a crank on said shaft for winding said spring, means for releasably holding said shaft against spring unwinding, a clutch having first and second elements for connecting said shaft to an engine crankshaft, means for mounting said starter housing on an engine housing, and connecting means between said shaft and one of said clutch elements, said connecting means having a contact area of adjustable length in the direction of the starter shaft axis.

2. In a spring starter for mounting on an internal combustion engine having a housing and a crankshaft, a starter housing of generally flat circular shape, a starter shaft centrally and rotatably mounted in said starter housing, a torsion spring in said housing having an outer end fixed to the housing and an inner end connected to said shaft, a crank on the upper end of said starter shaft, pawl and ratchet means for releasably holding said starter shaft against unwinding of said spring, a one-way clutch having a first element secured to said engine crankshaft, a second element in said one-way clutch, a non-circular recess in the lower end of said starter shaft, an upward extension on said second clutch element interfitting with said recess, and means for mounting said starter housing a fixed distance above said engine housing.

3. The combination according to claim 2, said crank being mounted for radial sliding movement on said shaft between a winding position and a release position, means on said starter shaft and crank non-rotatably connecting the starter shaft and crank when the crank is in its winding position, and means permitting the relative rotation between the starter shaft and crank when the crank is shifted to its release position.

4. The combination according to claim 3, further provided with a release member on said crank engageable with said pawl and ratchet means to release said means in response to rotation of the crank when in its release position.

5. The combination according to claim 4, said crank having an inner crank portion and an outer crank portion in foldable relation.

6. The combination according to claim 4, said release means comprising a member carried by said crank, said pawl and ratchet means comprising a ratchet secured to said shaft and a pawl mounted on a stationary pivot, said release member being engageable with said pawl.

7. In a spring starter, a shaft, a torsion spring connected to said shaft, a non-circular portion on said shaft, a crank having a slot with a narrow portion interengageable with said non-circular shaft portion and a wide portion rotatable with respect to said non-circular portion, said crank being shiftable between a winding position in which said narrow slot portion engages said shaft portion and a release position in which said wide slot portion surrounds said shaft portion, releasable means for holding said shaft against spring unwinding, and means responsive to shifting of said crank to its winding position for disenabling said releasable means.

8. The combination according to claim 7, further provided with means responsive to shifting of said crank to its release position for enabling said releasable means.

9. The combination according to claim 8, said releasable means comprising a ratchet mounted on said shaft and a pawl mounted on a stationary pivot, said enabling and disenabling means comprising a member carried by said crank and movable into releasing engagement with said pawl only when said crank is in its releasing position.

10. The combination according to claim .9, further provided with a housing for said spring, said crank being spaced from said housing, said pawl being mounted on said housing, said pawl releasing member being mounted on said crank and extending toward said housing.

11. The combination according to claim 10, further provided with a portion on said releasing member engageable with a portion of said pawl to limit releasing rotation of said crank when in its release position.

12. The combination according to claim 7, further provided with cooperating guide means on said shaft and crank to maintain radial movement of the crank when shifted between its winding and releasing positions.

:13. The combination according to claim 12, said guide means comprising a pair of substantially parallel flanges on said crank, and a disk secured to said shaft and disposed between said flanges.

14. In a spring starter for use with any of various internal combustion engines having crankshafts with externally threaded outer ends, a starter shaft, 2. spring connected to said shaft, a crank connected to said shaft for winding said spring, releasable holding means for preventing rotation of said starter shaft due to unwinding of said spring, a one-way clutch between said starter shaft and crankshaft, said one-way clutch comprising a first element with an internally threaded hub connectable to said crankshaft and a second element connected to said starter shaft, and an adaptor for securing said first clutch element to any of said various crankshafts, said adaptor comprising a tubular member having external threads at opposite ends matching the internal thread of said clutch element hub, a first internal thread at one end adapted to match one type of engine crankshaft thread, and an in- 7 ternal thread at the other end adapted to match another type of crankshaft thread.

15. In a spring starter for use in combination with an internal combustion engine having an engine housing and an engine crankshaft accessible through an apertured portion of said engine housing, a starter housing of generally flat circular shape, legs of fixed length on the underside of said starter housing adapted to be secured to said engine housing surrounding the apertured portion thereof, a starter shaft centrally and rotatably mounted in said starter housing and extending from the upper and lower ends thereof, a torsion spring in said housing surrounding said shaft, the outer end of said spring being fixed to said housing, the inner end of said spring being connected to said starter shaft, a ratchet non-rotatably mounted on said shaft above said housing, a pawl on a stationary pivot on said housing and engageable with said ratchet to prevent unwinding rotation of the starter shaft, a non-circular portion on said shaft above said ratchet, a crank on said non-circular shaft portion having a slot within which the non-circular shaft portion is disposed, said crank being shiftable radially between a winding position and a release position, a narrow portion of said slot non-rotatably connectable to said non-circular shaft portion when the crank is in its Winding position, a wide portion on said slot surrounding said non-circular shaft portion when the crank is in its release position to permit relative rotation between the crank and starter shaft, a downward extension on said crank engageable with said pawl in response to rotation of the crank when in its release position to retract said pawl from said ratchet, a one-way clutch having a first element securable to said engine crankshaft, a second element on said oneway clutch having an upward extension of non-circular cross-sectional shape, and a recess in the lower end of said 8 starting shaft of complementary non-circular cross-sectional shape and receiving said clutch element extension therein.

16. In combination, a spring starter having a housing, legs for mounting said housing on an engine housing at a fixed distance therefrom, a spring in said starter housing, a shaft rotatably mounted in said starter housing and connected to said spring, a crank for rotating said shaft to wind said spring, means for releasably holding said shaft against rotation by unwinding of said spring, a oneway clutch having a first element securable to an engine crankshaft, and a second element in said one-way clutch having a telescoping non-rotatable connection with said starter shaft, said telescoping connection comprising a non-circular recess in one end of said starter shaft, and an extension on said second clutch element having a cross-sectional shape complementary to and interfitting with said recess.

References Cited in the file of this patent UNITED STATES PATENTS 298,686 Gardner May 13, 1884 786,516 Phelan Apr. 4, 1905 2,511,908 Forbes June 20, 1950 2,564,787 Mack Aug. 21, 1951 2,568,359 Palfi Sept. 18, 1951 2,721,482 Shank et al Oct. 25, 1955 2,922,411 Skinner Jan. 26, 1960 2,950,780 De Millar Aug. 30, 1960 2,987,057 Kopp June 6, 1961 2,990,827 Kawecki July 4, 1961 2,999,489 Coughlin et al. t Sept. 12, 1961 2,999,490 Hamman Sept. 12, 1961 

1. IN COMBINATION, A SPRING STARTER HAVING A HOUSING A SPRING WITHIN SAID HOUSING, A SHAFT ROTATABLY MOUNTED IN SAID HOUSING AND CONNECTED TO SAID SPRING, A CRANK ON SAID SHAFT FOR WINDING SAID SPRING, MEANS FOR RELEASABLY HOLDING SAID SHAFT AGAINST SPRING UNWINDING, A CLUTCH HAVING FIRST AND SECOND ELEMENTS FOR CONNECTING SAID SHAFT TO AN ENGINE CRANKSHAFT, MEANS FOR MOUNTING SAID STARTER HOUSING ON AN ENGINE HOUSING, AND CONNECTING MEANS BETWEEN SAID SHAFT AND ONE OF SAID CLUTCH ELEMENTS, SAID CONNECTING MEANS HAVING A CONTACT AREA OF ADJUSTABLE LENGTH IN THE DIRECTION OF THE STARTER SHAFT AXIS. 